# encoding:utf-8
import os
import json
from time import sleep

filename = 'student_data.txt'


def main_interface():
    while True:
        print('=' * 25)
        print("学生信息管理系统")
        print('1.查看所有学生')
        print('2.添加学生')
        print('3.删除学生')
        print('4.修改指定学生的信息')
        print('0.退出系统')
        print('=' * 25)
        chance = int(input('请选择:'))
        if chance == 1:
            see_student()
        elif chance == 2:
            os.system('cls')
            print('='*25)
            print('学生添加模块')
            print('1.保存信息')
            print('2.退出当前模块，返回上一级')
            print('='*25)
            add_student()
        elif chance == 3:
            del_student()
        elif chance == 4:
            modify_student()
        elif chance == 0:
            print('谢谢使用!')
            break


def add_student():
    '''
    添加学生
    :return:
    '''

    while True:
        students = {}
        name = input('请输入学生姓名:')
        age = input('请输入学生年龄:')
        phone_num = input("请输入你的的电话:")
        student = {"name": name, "age": age, "phone_num": phone_num}
        students.update(student)
        flag = int(input('请输入你的操作:'))
        if flag == 1:

            # 当flag=1时保存当前输入的信息
            print('保存成功')
            sleep(2)
            open_file(students)
        elif flag == 2:
            # 当flag==2时退出添加学生的功能，并保存学生信息
            print('保存成功')
            open_file(students)
            sleep(2)
            break


def get_all_student():
    '''
    获取所有学生信息
    '''
    student_list = []
    dic_stu = {}
    with open(filename, 'r+', encoding='utf-8', errors='ignore') as file_obj:
        students = file_obj.readlines()
        for student in students:
            if student.startswith(u'\ufeff'):
                student = student.encode('utf-8')[3:].decode('utf-8').replace('\'', '\"')
                dic_stu = json.loads(student, encoding='utf-8')

            else:
                student = student.encode('utf-8').decode('utf-8').replace('\'', '\"')
                dic_stu = json.loads(student, encoding='utf-8')
            student_list.append(dic_stu)

    return student_list


def see_student():
    '''
    查看学生信息
    :return:
    '''
    student_list = get_all_student()
    for student in student_list:
        for key in student.keys():
            print('%s=%s' % (key, student[key]), end=' ')
        print()
    sleep(2)

def del_student():
    '''
    删除学生信息
    :return:
    '''
    student_list = get_all_student()
    num=len(student_list)   #记录学生数
    name = input('请输入你要删除学生的姓名:')
    for student in student_list:
        for key in student.keys():
            if student[key] == name:
                student_list.remove(student)
                print('删除成功!!!')
                sleep(2)
                break
    '''
    将删除了指定的学生的信息写回文件中，但是要先将文件里情空
    '''
    if(num>len(student_list)):
        #判断是否删除了
        writeback_file(student_list)
    else:
        print('你要删除的学生不存在!!!')
        sleep(2)

    '''
    重新显示新文件里的信息
    '''


def modify_student():
    '''
    修改学生信息的方法
    '''
    # 1.先获取所有学生信息
    student_list = get_all_student()
    # 2.获取要修改的学生名字
    name = input('请输入你要修改学生的姓名:')
    # 3.遍历学生列表，查看是否存在该学生
    for student in student_list:
        for key in student:
            if student[key] == name:
                name = input('请输入新的姓名:')
                age = input('请输入新的年龄:')
                phone_num = input('请输入新的电话号码:')
                student_list[student_list.index(student)] = {"name":name,"age":age,"phone_num":phone_num}
                print('修改成功!!')
                sleep(2)
                writeback_file(student_list)
                return 0
    print('对不起，你输入的学生不存在!!')
    sleep(2)

def writeback_file(student_list):
    '''
    数据回写文件的方法
    '''
    with open(filename, 'w', encoding='utf-8') as _:
        for student in student_list:
            open_file(student)


def open_file(students):
    with open(filename, 'a+', encoding='utf-8') as file_obj:
        # for key in students:
        #     file_obj.write(key+":"+students[key]+'\n')
        file_obj.write(str(students) + '\n')


if __name__ == '__main__':
    '''
    主函数
    '''
    main_interface()
    # print(dict('{1:2,3:4}'))
    # print(json.loads('{"1":2, 2:3}', encoding='utf-8'))